The present invention relates to a radiation penetration system, such as, e.g., computer tomographs or the like, and a calibration of such systems.
Radiation penetration systems frequently operate using X-radiation. Flat-panel detectors of radiation penetration systems frequently have a screen, like, e.g., a scintillator screen for X-ray-sensitive flat-panel detectors, which is then recorded using one or several optical cameras. In this way, for example, X-ray cameras exists which are used, for example, in digital radioscopy or computer tomography for quality control of products or for metrology.
Due to their setup, conventional imaging X-ray flat-panel cameras, such as, e.g., flat screen detectors on the basis of amorphous silicon, generally comprise square pixels which fill the active detector surface more or less completely, i.e. completely sample the scintillator surface. The alignment of the lines and columns and their spacing are predetermined depending on the design in these X-ray cameras and cannot be changed. An exception is the so-called binning, i.e. combining several neighboring pixels into one image point, wherein the resolution and the amount of data may be reduced and the signal-to-noise ratio may be improved.
For certain applications of these X-ray cameras, it is necessitated to adjust the camera in a mechanically exact way in an assembly such that the lines and columns have a defined orientation with respect to other components of the assembly, for example the mechanical positioning axes. With decreasing pixel size or increasing resolution of the camera, also requirements on the accuracy and stability of mechanical adjustment between the camera and the other assembly components increase, such as, e.g., the manipulator, which includes, for example, a robot arm, a C-frame or the like.
The adjustment of radiation penetration systems has up to now been cost- and time-consuming for this reason and has included an iterative and approximative process in which radiation penetrations were executed alternatingly on calibration objects and the thus acquired measurements were used for readjusting the flat-panel detector.
It is the object of the present invention to provide a radiation penetration system and a method and a device for calibrating the same so that an improved tradeoff between adjustment on the one hand and measurement accuracy on the other hand may be acquired, i.e., for example, the same measurement accuracy with less adjustment effort, and this, in turn, with little additional hardware and/or software expenditure.